I like the first one a little more, i find it more atmospherical, also the background looks more like an environment around the object while in the second one the background looks more like a picture on a wall because the focus object has less room to breathe.
But i also think it depends on the purpose you want the render to fulfill. First one is clearly the better one to display the weapon itself. But the second one is better to give a glimpse of the universe the whole scene plays in. In my eyes the additional objects (cables/lights/batteries) don´t really add anything that would be missing in the first picture.
Also prefer the hexagonal shield from version 1 but the red laserbeam from version 2 looks way more powerful and cooler! Thanks for sharing! 